Y being a hydrogen or a carbon atom

Sulfonic acids; Halides, esters, or anhydrides thereof > Sulfonic acids > having sulfo groups bound to carbon atoms of six-membered aromatic rings of a carbon skeleton > containing nitrogen atoms, not being part of nitro or nitroso groups, bound to the carbon skeleton > the carbon skeleton being further substituted by doubly-bound oxygen atoms > the carbon skeleton containing carbon atoms of quinone rings > at least one of the nitrogen atoms being part of any of the groups X being a hetero atom, Y being any atom > Y being a hydrogen or a carbon atom

Sulfonic acids; Halides, esters, or anhydrides thereof > Sulfonic acids > having sulfo groups bound to carbon atoms of six-membered aromatic rings of a carbon skeleton > containing nitrogen atoms, not being part of nitro or nitroso groups, bound to the carbon skeleton > the carbon skeleton being further substituted by doubly-bound oxygen atoms > the carbon skeleton containing carbon atoms of quinone rings > at least one of the nitrogen atoms being part of any of the groups [IMAGE cpc-sch-C07C-0976.gif], X being a hetero atom, Y being any atom > Y being a hydrogen or a carbon atom